Embodiments relate to a semiconductor device and a method for manufacturing the same.
A semiconductor device may include a transistor having a source/drain and a gate formed at a device area defined through a LOCOS (local oxidation of silicon) process or an STI (shallow trench isolation) process.
For example, a semiconductor substrate may be formed with isolation layers that may isolate devices. In addition, device areas of the semiconductor substrate may be formed with a gate, for example, including a gate oxide layer and a gate poly. A spacer, for example including an insulting layer, may be formed at sidewalls of the gate poly.
In addition, an lightly doped drain (LDD), into which low-density impurities that may have a conductive type opposite to that implanted into the semiconductor substrate, may be formed in a lower part of the gate oxide layer of the semiconductor substrate. A source/drain, into which high-density impurities that may have a conductive type identical to that implanted into the LDD, may be formed at an area of the semiconductor substrate adjacent to the LDD.
A semiconductor device having the above structure may be scaled down to accommodate the high level of integration and miniaturization of semiconductor devices. However, since many processes may need to be performed to manufacture a semiconductor device having an LDD structure including a small gate width, a production process for a semiconductor device may be degraded.
In addition, overlap capacitance may be created where the LDD overlaps with a gate.